A FLUKE networks DTX 1800 Cable Analyzer és DTX Fiber Modules

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1 A FLUKE networks DTX 1800 Cable Analyzer és DTX Fiber Modules Rövidített leírás és kezelési utasítás The DTX Series CableAnalyzers are rugged, hand-held instruments used to certify, troubleshoot, and document copper and fiber cabling installations. The testers feature the following: The DTX-1800 certifies twisted pair and coaxial cabling to Class F limits (600 MHz).and Category 6 cabling. Color display clearly indicates PASS/FAIL results. Automatic diagnostics report distance to and likely causes of common faults. Optional fiber modules let you certify multimode and singlemode fiber optic cabling A műszer fő egységének kezelőszervei

2 Fényvezető kábelek csatlakoztatása

3 Mérési összeállítás és a mérés menete UTP mérésnél

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5 Mérési összeállítás és a mérés menete fényvezető kábel mérésnél

6 Fogalmak, definiciók, szabványok Autotest Autotest is the most frequently used function in LAN cable testing. Autotest performs all of the tests necessary to qualify the cabling you are testing. When the Autotest is complete, the tests that were run are listed with the overall result for each test. You can also view detailed results for each test. Results from Autotests can be saved for printing or transmission to a host computer. Headroom: Reports the worst-case margin for a parameter determined by selected test standard. This may be NEXT, ACR, PSNEXT, or another measurement. Wire Map: Tests for opens, shorts, crossed pairs, reversed wires, and split pairs. NEXT and ELFEXT: Tests twisted pair cabling for near-end crosstalk (NEXT) and equal level far-end crosstalk (ELFEXT). Length: Displays the length of twisted pairs in feet or meters. Propagation Delay: Measures the times taken for a signal to travel the length of each cable pair. Delay Skew: Calculates the differences in propagation delays between the cable pairs. Impedance: Measures the impedance of each cable pair. If impedance anomalies are detected, the test reports the largest anomaly detected on each cable pair. Attenuation: Measures the attenuation of each cable pair. DC Resistance: Measures the loop resistance of each cable pair. ACR: Calculates the ratio of attenuation to crosstalk for all combinations of cable pairs. RL (Return Loss): Measures signal loss due to signal reflections in the cabling. PSNEXT (Power Sum NEXT): For each cable pair, PSNEXT is calculated as the sum of the NEXT from all other pairs. PSELFEXT (Power Sum ELFEXT): For each cable pair, PSELFEXT is calculated using the sum of the FEXT from the other pairs. PSACR (Power Sum ACR): For each cable pair, PSACR is calculated using the sum of the NEXT from the other pairs.

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8 RL (return loss) is the difference between the power of a transmitted signal and the power of the signal reflections caused by variations in the cable s impedance. A RL plot indicates how well a cable s impedance matches its rated impedance over a range of frequencies. High RL values mean a close impedance match, which results in a large difference between the powers of transmitted and reflected signals. Cables with high RL values are more efficient at transmitting LAN signals because little of the signal is lost in reflections. HDTDR is a measurement technique used to determine cabling length and characteristic impedance and to locate faults along the cabling. Time Domain Reflectometry is sometimes referred to as cable radar because it involves analyzing signal reflections in the cabling. If a signal traveling through cabling encounters an abrupt change in impedance, some or all of the signal is reflected back to the source. The timing, size, and polarity of the reflected signals indicate the location and nature of impedance anomalies in the cabling. The test tool applies very short (2 ns) test pulses to the cabling under test. The short pulses help the test tool resolve smaller anomalies, resulting in more accurate distance-to-fault measurements and better definition of faults on plots. The test is run from both ends of the cabling (if the remote is used) for improved visibility of far-end anomalies.